This invention deals generally with door lock alarm systems and more particularly with an improved anti-theft door lock and alarm for a merchandise container, such as a jewelry show case.
U.S. Pat. No. 3,686,660 issued Aug. 22, 1972 to Massover et al, which represents the most pertinent prior art known to applicant, discloses a merchandise show case equipped with an audible alarm system which is activated when an authorized attendant leaves his usual station behind the show case with the access door of the show case in an open position. However, the alarm system of the aforesaid Massover et al patent makes no provision for the automatic locking of the access door of the show case when the attendant leaves his usual station and the deactivation of the alarm system in response to the locking of the show case door.
Accordingly, the present invention may be considered an improvement over the show case alarm system disclosed in the aforesaid Massover et al patent, in that it combines an automatic door lock with the alarm or signal, and provides either for the automatic locking of the door of the show case or the activation of the signal if the attendant should leave his usual station with the door open or slightly ajar.